Methods and devices for obstructing and aspirating lung tissue segments

ABSTRACT

The present invention provides improved methods, systems, devices and kits for performing lung volume reduction in patients suffering from chronic obstructive pulmonary disease or other conditions where isolation of a lung segment or reduction of lung volume is desired. The methods are minimally invasive with instruments being introduced through the mouth (endotracheally) and rely on isolating the target lung tissue segment from other regions of the lung. Isolation is achieved by deploying an obstructive device in a lung passageway leading to the target lung tissue segment. Once the obstructive device is anchored in place, the segment can be aspirated through the device. This may be achieved by a number of methods, including coupling an aspiration catheter to an inlet port on the obstruction device and aspirating through the port. Or, providing the port with a valve which allows outflow of gas from the isolated lung tissue segment during expiration of the respiratory cycle but prevents inflow of air during inspiration. In addition, a number of other methods may be used. The obstructive device may remain as an implant, to maintain isolation and optionally allow subsequent aspiration, or the device may be removed at any time.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] The present application is a continuation of U.S. patentapplication Ser. No. 09/699,302 (Attorney Docket No. 017534-001200),filed Oct. 27, 2000, which is related to co-pending U.S. patentapplication Ser. No. 09/699,313 (Attorney Docket No. 017534-001300),also filed Oct. 27, 2000, the full disclosures of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates generally to medical methods,systems, and kits. More particularly, the present invention relates tomethods and apparatus for effecting lung volume reduction by aspiratingisolated segments of lung tissue.

[0004] Chronic obstructive pulmonary disease is a significant medicalproblem affecting 16 million people or about 6% of the U.S. population.Specific diseases in this group include chronic bronchitis, asthmaticbronchitis, and emphysema. While a number of therapeutic interventionsare used and have been proposed, none are completely effective, andchronic obstructive pulmonary disease remains the fourth most commoncause of death in the United States. Thus, improved and alternativetreatments and therapies would be of significant benefit.

[0005] Of particular interest to the present invention, lung function inpatients suffering from some forms of chronic obstructive pulmonarydisease can be improved by reducing the effective lung volume, typicallyby resecting diseased portions of the lung. Resection of diseasedportions of the lungs both promotes expansion of the non-diseasedregions of the lung and decreases the portion of inhaled air which goesinto the lungs but is unable to transfer oxygen to the blood. Lungreduction is conventionally performed in open chest or thoracoscopicprocedures where the lung is resected, typically using stapling deviceshaving integral cutting blades.

[0006] While effective in many cases, conventional lung reductionsurgery is significantly traumatic to the patient, even whenthoracoscopic procedures are employed. Such procedures often result inthe unintentional removal of healthy lung tissue, and frequently leaveperforations or other discontinuities in the lung which result in airleakage from the remaining lung. Even technically successful procedurescan cause respiratory failure, pneumonia, and death. In addition, manyolder or compromised patients are not able to be candidates for theseprocedures. For these reasons, it would be desirable to provide improvedmethods, systems, and kits for performing lung volume reduction whichovercome at least some of the shortcomings noted above.

[0007] 2. Description of the Background Art

[0008] WO 99/01076 and corresponding U.S. Pat. No. 5,957,919 describesdevices and methods for reducing the size of lung tissue by applyingheat energy to shrink collagen in the tissue. In one embodiment, air maybe removed from a bleb in the lung to reduce its size. Air passages tothe bleb may then be sealed, e.g., by heating, to fix the size of thebleb. WO 98/48706 describes a plug-like device for placement in a lungair passage to isolate a region of lung tissue, where air is not removedfrom the tissue prior to plugging. WO 98/49191 describes the use ofsurfactants in lung lavage for treating respiratory distress syndrome.U.S. Pat. No. 5,925,060 may also be of interest.

[0009] Patents and applications relating to lung access, diagnosis, andtreatment include U.S. Pat. Nos. 5,957,949; 5,840,064; 5,830,222;5,752,921; 5,707,352; 5,682,880; 5,660,175; 5,653,231; 5,645,519;5,642,730; 5,598,840; 5,499,625; 5,477,851; 5,361,753; 5,331,947;5,309,903; 5,285,778; 5,146,916; 5,143,062; 5,056,529; 4,976,710;4,955,375; 4,961,738; 4,958,932; 4,949,716; 4,896,941; 4,862,874;4,850,371; 4,846,153; 4,819,664; 4,784,133; 4,742,819; 4,716,896;4,567,882; 4,453,545; 4,468,216; 4,327,721; 4,327,720; 4,041,936;3,913,568 3,866,599; 3,776,222; 3,677,262; 3,669,098; 3,542,026;3,498,286; 3,322,126; WO 95/33506, and WO 92/10971.

[0010] Lung volume reduction surgery is described in many publications,including Becker et al. (1998) Am. J Respir. Crit. Care Med.157:1593-1599; Criner et al. (1998) Am. J Respir. Crit. Care Med.157:1578-1585; Kotloffet al. (1998) Chest 113:890-895; and Ojo et al.(1997) Chest 112:1494-1500.

[0011] The use of mucolytic agents for clearing lung obstructions isdescribed in Sclafani (1999) AARC Times, January, 69-97. Use of aballoon-cuffed bronchofiberscope to reinflate a lung segment sufferingfrom refractory atelectasis is described in Harada et al. (1983) Chest84:725-728.

SUMMARY OF THE INVENTION

[0012] The present invention provides improved methods, systems, devicesand kits for performing lung volume reduction in patients suffering fromchronic obstructive pulmonary disease or other conditions whereisolation of a lung segment or reduction of lung volume is desired. Thepresent invention is likewise suitable for the treatment ofbronchopleural fistula. The methods are minimally invasive withinstruments being introduced through the mouth (endotracheally) and relyon isolating the target lung tissue segment from other regions of thelung. Isolation is achieved by deploying an obstructive device in a lungpassageway leading to the target lung tissue segment. Once theobstructive device is anchored in place, the segment can be aspiratedthrough the device. This may be achieved by a number of methods,including coupling an aspiration catheter to an inlet port on theobstruction device and aspirating through the port. Or, providing theport with a valve which allows outflow of gas from the isolated lungtissue segment during expiration of the respiratory cycle but preventsinflow of air during inspiration. In addition, a number of other methodsmay be used. The obstructive device may remain as an implant, tomaintain isolation and optionally allow subsequent aspiration, or thedevice may be removed at any time. Likewise, the device may biodegradeover a period of time.

[0013] The obstruction device may take a variety of forms to allowdelivery, deployment and anchoring in a lung passageway. Delivery iscommonly performed with the use of a minimally invasive device, such asa flexible bronchoscope or an access catheter. The flexible bronchoscopemay be utilized with a sheath having an inflatable cuff disposed nearits distal end, a full description of which is provided in co-pendingapplication [Attorney Docket No. 017534-001300], assigned to theassignee of the present invention and incorporated by reference for allpurposes. When using such a sheath, the scope is introduced into a lumenin the sheath to form an assembly which is then introduced to the lungpassageway. The cuff may then be inflated to occlude the passageway.Similarly, an access catheter may be used which may be steerable orarticulating, may include an inflatable balloon cuff near its distal endand may include a number of lumens for balloon inflation, tracking overa guidewire, and optical imaging, to name a few. The obstruction deviceis typically housed within a lumen of the access catheter, bronchoscope,sheath or suitable device, mounted near the distal tip of the catheteror carried by any method to the desired lung passageway leading to thetarget lung tissue segment. Therefore, the obstruction device must besized appropriately for such delivery and is typically designed toexpand upon deployment to anchor within the lung passageway. Hereinafterthe present invention is depicted in relation to use with an accesscatheter, however it may be appreciated that any suitable device may beused.

[0014] In a first aspect of the present invention, the obstructiondevice comprises a structural support which expands and thereby anchorsthe device in the lung passageway. Such supports may comprise a numberof configurations for a variety of expansion techniques. For example,the structural supports may allow the obstruction device to coil, roll,bend, straighten or fold in a cone, rod, cylinder or other shape fordelivery. Then, once positioned in a desired location, the obstructiondevice may be released and expanded to anchor the device in thepassageway. Such expansion may be unaided, such as in the release of acompressed structure to a pre-formed expanded position. Or, suchexpansion may be aided, such as with the use of an inflatable balloon orcuff. In some cases, a balloon or inflatable member may be incorporatedinto the obstruction device and may remain inflated to occlude thepassageway. This may be provided in combination with structural supportsor an inflatable balloon or similar device may be used without suchsupport.

[0015] The structural supports may be comprised of any type of wire,particularly superelastic, shape-memory or spring tempered wire, or anytype of polymer or a suitable material. The balloon or inflatable membermay be comprised of any flexible, polymeric material suitable for such apurpose. The member may be inflated with gas or liquid as desired, or itmay be inflated with an expanding foam or similar material. Likewise, itmay be inflated or injected with an adhesive. Such an adhesive mayexpand the member and/or rigidify the member to reduce the likelihood ofcollapse. Further, the adhesive may additionally serve to bond thedevice to the walls of the lung passageway to increase anchorage. Inaddition, the device may be impregnated or coated with an antibioticagent, such as silver nitrate, or similar agent for delivery of theagent to the lung passageway. Such delivery may occur by any applicablemeans.

[0016] When structural supports are present, such supports may comprisea variety of designs. In a first embodiment, the structural supportscomprise radial segments which expand to fill the passageway andlongitudinal segments which rest against the walls of the passageway tohelp anchor the device. In a second embodiment, the structural supportscomprise a mesh which expands to fill the passageway. In a thirdembodiment, the structural supports comprise a helically or spirallywound wire which also expands to contact the walls of the passageway andanchor the device. In each of these embodiments, the structural supportmay be connected with or encapsulated in a sack comprised of a thinpolymeric film, open or closed cell foam or other suitable material toprovide a seal against walls of the lung passageway and obstruct airflowthrough the device. The sack material may also be infused with anadhesive, sealant or other material to improve obstruction of the airwayand possibly improve adhesion to the airway walls.

[0017] In a second aspect of the present invention, the obstructiondevice may further comprise ports for aspiration through the device.This may allow access to the collapsed lung segment at a later time, forexample, in the case of an infection. Typically, the obstruction devicewill have an inlet port located near the proximal end of the device,away from the isolated lung tissue segment. Such a port is thusaccessible by minimally invasive devices, such as an aspirationcatheter, which may be advanced through the bronchial passageways.Optionally, an outlet port may be located near the distal end of theobstruction device. The ports may comprise a variety of designs for anumber of purposes.

[0018] In a first embodiment, the port comprises a self-sealing septum.Such a septum may comprise a solid membrane or a pre-cut membrane.Aspiration through the port may be achieved with the use of anaspiration catheter having an access tube or penetrating element at itsdistal end. Such a catheter may be advanced to the site of theobstruction device itself or with the use of an access catheter. Theseptum may be penetrated, either pierced through a solid membrane orpassed through the cuts of a pre-cut membrane, by the access tube.Depending on the design of the obstruction device, the inlet port andoptionally the outlet port may be penetrated in this fashion. Aspirationmay be achieved through the access tube and aspiration catheter towithdraw gases and/or liquids from the isolated lung tissue segment andpassageway. Optionally, prior to aspiration, a 100% oxygen,Helium-Oxygen mixture or low molecular weight gas washout of the lungsegment may be performed by introducing such gas through the accesstube, such as by a high frequency jet ventilation process. In this case,aspiration would remove both the introduced gas and any remaining gas.Similarly, liquid perfluorocarbon or certain drugs, such as antibiotics,retinoic acid and hyaluronic acid, may be introduced prior toaspiration. In most cases, aspiration will at least partially collapsethe lung segment. Upon removal of the aspiration catheter from the port,the septum may self-seal or it may be further sealed with a sealant orother sealing means for later access or permanent closure.

[0019] When the self-sealing septum comprises a pre-cut membrane,aspiration through the port may alternatively be achieved by coupling anaspiration catheter to the obstructive device. Coupling may compriseengaging the aspiration catheter to the port or sliding a couplingmember or the aspiration catheter over the port to form a seal. Ineither case, suction through the aspiration catheter may allow gasesand/or liquids to pass through the cuts in the membrane to be withdrawnfrom the isolated lung tissue segment and passageway. Again, this willat least partially collapse the lung segment. Likewise, upon removal ofthe aspiration catheter from the port, the septum may self-seal or itmay be further sealed with a sealant or other sealing means for lateraccess or permanent closure.

[0020] In a second embodiment, the port comprises a unidirectionalvalve. Such a valve may comprise a port covered by a flexible layerwhich is attached to the port by at least one point of connection.Movement of the layer away from the port opens the valve and movementagainst the port closes the valve. Wherein the flexible layer is solid,movement of the layer away from the port allows gas to flow between thepoints of connection and around the edges of the flexible layer.Alternatively, the flexible layer may have holes therethrough. In thiscase, the port may also comprise a partition having holes which are notaligned with the holes in the flexible layer. Movement of the layer awayfrom the port allows gas to flow through the holes in the partition andout through the holes in the flexible layer. When the layer movesagainst the partition, the holes will be covered closing the valve.Other valve designs include a spring-loaded ball valve or a biasedpre-loaded diaphragm valve.

[0021] Aspiration through a unidirectional valve may be achieved by anumber of methods. Again, the port may be accessed by advancing anaspiration catheter or similar device through the bronchial passagewaysto the site of the obstruction device. This may optionally be achievedwith the use of an access catheter. The aspiration catheter may beplaced near the valve or engaged to the valve, wherein suction or vacuumapplied through the catheter opens the valve. If the aspiration catheteris not engaged to the valve, adequate suction to open the valve may beachieved by occluding the passageway proximal to the point of suctionwhich is typically the distal end of the aspiration catheter. Suchocclusion may be achieved by inflating a balloon or occlusion devicemounted on the distal end of the aspiration catheter or mounted on anaccess catheter. In either case, the vacuum may draw the flexible layeraway from the port, allowing gases and/or liquids to flow out from theisolated lung segment, through the valve and into the aspirationcatheter. Alternatively, aspiration through a unidirectional valve maybe achieved naturally during respiration. Pressure changes may open thevalve during expiration as gases flow out from the isolated lungsegment. Reverse pressure changes, during inspiration, may close thevalve preventing gases from flowing into the isolated segment. This mayreduce the amount of gas trapped in the terminal segment over time andthus at least partially collapse the lung segment. Similarly, aspirationthrough the unidirectional valve may be achieved by external mechanicalpressure on the lung to force out of the lung segment and through thevalve. Again, reverse pressure changes upon recoil of the lung wouldclose the valve preventing gases from flowing into the isolated segment.

[0022] In a third aspect of the present invention, the obstructiondevice may comprise a blockage device which is deployed in a lungpassageway to close the airway. Such a blockage device may be of similardesign as previously described obstruction devices as it may besimilarly delivered, deployed and anchored within a lung passageway.Thus, embodiments of the blockage device typically comprise expandablesupport structures. For example, in one embodiment the support structurecomprises a coil. And, in a second embodiment, the support structurecomprises a mesh. Again, the support structures may be connected to orencased in a polymer film or sack to provide a seal against the walls ofthe lung passageway and obstruct airflow through the device. Typicallythe blockage device will be placed in the passageway after the terminallung segment has been aspirated by other methods. This will seal off thelung segment and maintain lung volume reduction. Alternatively, theblockage device may be placed in the passageway before the terminal lungsegment has been aspirated. In this case, air trapped in the lungsegment may be absorbed over time and would eventually collapse, aprocess known as absorption atelectasis. This process may be enhanced byinsufflating the lung segment with 100% oxygen, a Helium-Oxygen mixtureor low molecular weight gas prior to placing the blockage device. Suchenhancement may promote complete collapse of the lung segment. In anycase, the blockage device may optionally be later removed if it is sodesired.

[0023] Methods of the present invention include the utilization of anobstruction device to achieve lung volume reduction. As described above,methods include delivery, deployment and anchoring of an obstructiondevice in a lung passageway leading to a target lung tissue segment. Atleast partial collapse of the terminal lung tissue segment may beachieved by aspirating the segment through the obstruction devicedeployed in the passageway. Aspiration may be accomplished with the useof an aspiration catheter or similar device through a port on theobstruction device. Also described above, when the port comprises aunidirectional valve, aspiration and eventual lung volume reduction maybe accomplished by the opening and closing of the valve in response therespiratory cycle. In addition, methods of the present invention includedeployment of a blockage device in a lung passageway leading to aterminal lung tissue segment, as previously described.

[0024] Systems of the present invention may include any of thecomponents described in relation to the present invention. A particularembodiment of a system of the present invention comprises an accesscatheter and an obstruction device, as described above, wherein theobstruction device is introduceable by the access catheter. For example,the obstruction device may be houseable within a lumen of the accesscatheter for deployment out the distal end of the catheter, or theobstruction device may be mountable on the access catheter near itsdistal end. In either case, the obstruction device may be deployed andanchored within a lung passageway.

[0025] The methods and apparatuses of the present invention may beprovided in one or more kits for such use. The kits may comprise anobstruction device deployable within a lung passageway and instructionsfor use. Optionally, such kits may further include any of the othersystem components described in relation to the present invention and anyother materials or items relevant to the present invention.

[0026] Other objects and advantages of the present invention will becomeapparent from the detailed description to follow, together with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027]FIG. 1 is a perspective illustration of an access catheter usefulin the methods, systems, and kits of the present invention.

[0028]FIG. 2 is a cross-sectional view taken along line 2 to a FIG. 1.

[0029] FIGS. 3A-3F illustrate alternative cross-sectional views of theaccess catheter of FIG. 1.

[0030] FIGS. 4A-4C illustrate a steerable imaging guidewire which may beused to facilitate positioning of the access catheter used in themethods of the present invention.

[0031]FIG. 5A illustrates use of the access catheter of FIG. 1 foraccessing a target lung tissue segment according the to the methods ofthe present invention.

[0032]FIG. 5B illustrates use of a visualizing tracheal tube with theaccess catheter of FIG. 1 for accessing a target tissue segmentaccording the to the methods of the present invention.

[0033]FIG. 6 illustrates a method of deployment or delivery of anobstructive device.

[0034] FIGS. 7A-7B are perspective views of embodiments of obstructivedevices having, among other features, radial and longitudinal structuralsupports.

[0035]FIG. 8 is a perspective view of an embodiment of an obstructivedevice in a rolled configuration prior to release in a lung passageway.

[0036]FIG. 9 is a perspective View of an embodiment of a rolled,cylindrical shaped obstructive device in an expanded state within aflexible sack.

[0037]FIG. 10 illustrates an embodiment of a double conical shapedobstructive device.

[0038]FIG. 11 is a perspective view of an embodiment of an obstructivedevice having, among other features, a mesh structural support encasedby a polymer film.

[0039]FIG. 12 is a perspective view of an embodiment of an obstructivedevice having, among other features, a spiral structural support.

[0040]FIG. 13 is a perspective view of an embodiment of an obstructivedevice having a cone shape with an inlet port at the apex of the cone.

[0041] FIGS. 14A-14C illustrate embodiments of self-sealing septums ofthe present invention.

[0042]FIG. 15 illustrates a method of aspirating through an obstructivedevice by inserting an access tube through a septum of an inlet port.

[0043]FIG. 16 illustrates a method of aspirating through an obstructivedevice by contacting an aspiration catheter to an inlet port.

[0044]FIG. 17 illustrates a method of aspirating through an obstructivedevice by sliding the distal end of an aspiration catheter over an inletport.

[0045] FIGS. 18A-18C illustrate a method of deploying, anchoring andaspirating through an obstruction device while such a device isconnected to an aspiration catheter.

[0046]FIG. 19A is a front view of an embodiment of a unidirectionalvalve of the present invention. FIGS. 19B-19C are perspective views ofthe unidirectional valve of FIG. 19A in various stages of operation.

[0047] FIGS. 20-21 illustrate positioning of embodiments ofunidirectional valves of the present invention in a lung passageway.

[0048] FIGS. 22A-22B are front views of an embodiment of aunidirectional valve of the present invention.

[0049] FIGS. 23A-23B are perspective views of the unidirectional valveof FIGS. 21A-21B in various stages of operation.

[0050]FIG. 24 illustrates a method of deployment or delivery of ablockage device.

[0051]FIG. 25 illustrates an embodiment of a blockage device comprisinga coil encased in a polymer film.

[0052]FIG. 26 illustrates an embodiment of a blockage device comprisinga mesh connected to a polymer film.

[0053]FIG. 27 illustrates an embodiment of a blockage device comprisinga barb-shaped structure.

[0054]FIG. 28 illustrates an embodiment of a blockage device having acylindrical-type balloon with textured friction bands.

[0055]FIG. 29 depicts an embodiment of a blockage device comprising amulti-layer balloon which has an adhesive material between an outerlayer and an inner layer of the balloon.

[0056]FIG. 30 illustrates an embodiment of a blockage device which issimilar to that of FIG. 29, including openings in the outer layerthrough which adhesive may seep.

[0057]FIG. 31 illustrates a kit constructed in accordance with theprinciples of the present invention.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

[0058] Lung volume reduction is performed by collapsing a target lungtissue segment, usually within lobar or sub-lobular regions of the lungwhich receive air through a single lung passage, i.e., segment of thebranching bronchus which deliver to and receive air from the alveolarregions of the lung. Such isolated lung tissue segments are firstisolated and then collapsed by aspiration of the air (or other gases orliquids which may be present) from the target lung tissue segment. Lungtissue has a very high percentage of void volume, so removal of internalgases can reduce the lung tissue to a small percentage of the volumewhich it has when fully inflated, i.e. inflated at normal inspiratorypressures. The exemplary and preferred percentages for the volumereduction are set forth above.

[0059] The methods of the present invention will generally rely onaccessing the target lung tissue segment using an access catheteradapted to be introduced endotracheally into the bronchus of the lung.An exemplary access catheter 10 is illustrated in FIGS. 1 and 2 andcomprises a catheter body 12 having a distal end 14, a proximal end 16,and at least one lumen therethrough. Optionally, the catheter 10 furthercomprises an inflatable occlusion balloon 18 near its distal end. Inthis case, the catheter will have at least two lumens, a central lumen20 and a balloon inflation lumen 22. As shown in FIG. 2, the ballooninflation lumen 22 may be an annular lumen defined by inner body member24 and outer body member 26 which is coaxially disposed about the innerbody member. The lumen 22 opens to port 30 on a proximal hub 32 andprovides for inflation of balloon 18. The central lumen 20 opens to port36 on hub 32 and provides for multiple functions, including optionalintroduction over a guidewire, aspiration, introduction of secondarycatheters, and the like.

[0060] The dimensions and materials of access catheter 10 are selectedto permit endotracheal introduction and intraluminal advancement throughthe lung bronchus or passageway, optionally over a guidewire and/orthrough a primary tracheal tube structure (as illustrated in FIG. 4Bbelow). Suitable materials include low and high density polyethylenes,polyamides, nylons, PTFE, PEEK, and the like, particularly for the innertubular member 24. The outer member, including the occlusion balloon,can be made from elastomeric materials, such as polyurethane, lowdensity polyethylene, polyvinylchloride, silicone rubber, latex, and thelike. Optionally, portions of the outer tubular member 26 proximal tothe inflatable balloon can be made thicker and/or reinforced so thatthey do not dilate upon pressurization of the balloon. Exemplarydimensions for the access catheter 10 are set forth in the table below.ACCESS CATHETER DIMENSIONS Exemplary Preferred Inner Tubular OuterTubular Inner Tubular Outer Tubular Member Member Member Member OuterDiameter (mm) 0.4-4   0.6-4.5   1-1.5 2-4 Wall Thickness (mm) 0.05-0.25 0.5-0.25 0.1-0.2 0.15-0.25 Length (cm)  50-150 same 50-80 same BalloonLength (mm) 5-50 10-20 Balloon Diameter (mm) 2-20  6-15 (inflated)

[0061] The access catheter 10 may be modified in a number of ways, someof which are illustrated in FIGS. 3A-3F. For example, instead of aninner and outer coaxial tube construction, the catheter can be a singleextrusion having a catheter body 30 with a circular main lumen 32 and acrescent-shaped inflation lumen 34, as illustrated in FIG. 3A.Alternatively, catheter body 40 may be formed as a single extrusionhaving three lumens, i.e., a primary lumen 42 for receiving a guidewire,applying aspiration, and/or delivering secondary catheters. A secondlumen 44 can be provided for inflating the occlusion balloon, and athird lumen 46 can be provided as an alternative guidewire or aspirationlumen. Catheter body 50 comprising a main tubular body 52 having anouter layer 54 fused thereover to define a lumen 56 suitable for ballooninflation as shown in FIG. 3C. A primary lumen 58 is formed within themain tubular member 52. As a slight alternative, catheter body 60 can beformed from a primary tubular member 62, and a secondary tubular member64, where the tubular members are held together by an outer member 66,such as a layer which is applied by heat shrinking. The primary tubularmember 62 provides the main lumen 68 while secondary tube 64 provides asecondary lumen 70. The secondary lumen 70 will typically be used forballoon inflation, while the primary lumen 68 can be used for all otherfunctions of the access catheter.

[0062] Optionally, the access catheter in the present invention can beprovided with optical imaging capability. As shown in FIG. 3E, catheterbody 80 can be formed to include four lumens, typically by conventionalextrusion processes. Lumen 82 is suitable for passage over a guidewire.Lumens 84 and 86 both contain light fibers 88 for illumination. Lumen 90carries an optical wave guide or image fiber 92. Lumen 82 can be usedfor irrigation and aspiration, typically after the guidewire iswithdrawn. Balloon inflation can be effected through the space remainingand lumens 84 and 86 surrounding the light fibers 88. A second catheterbody 100 is formed as a coaxial arrangement of a number separate tubes.Outer tube 102 contains a separate guidewire tube 104 defining lumen 106which permits introduction over a guidewire as well as perfusion andaspiration after the guidewire is removed. Second inner tubular member110 will carry an optical image fiber 112 and a plurality of lightfibers 112 are passed within the remaining space 114 within the outertubular member. In both catheter constructions 80 and 100, forwardimaging can be effected by illuminating through the light fibers anddetecting an image through a lens at the distal end of the catheter. Theimage can be displayed on conventional cathode-ray or other types ofimaging screens. In particular, as described below, forward imagingpermits a user to selectively place the guidewire for advancing thecatheters through a desired route through the branching bronchus.

[0063] Usually, positioning of a guidewire through the branchingbronchus will be manipulated while viewing through the imagingcomponents of the access catheter. In this way, the access catheter canbe “inched” along by alternately advancing the guidewire and the accesscatheter. As an alternative to providing the access catheter withimaging, positioning could be done solely by fluoroscopy. As a furtheralternative, a steerable, imaging guidewire 300 (FIGS. 4A-4C) could beused. The guidewire 300 includes a deflectable tip 302 which can bedeflected in a single plane using push/pull ribbon 304. Usually, the tipwill comprise a spring 306 to facilitate deflection. In addition tosteerability, the guidewire 300 will include an optical imaging waveguide 310 and illuminating optical fibers 312, as best seen incross-sectional view of FIG. 4C. Thus, the guidewire 300 can be steeredthrough the branching bronchus to reach the target tissue segment usingits own in situ imaging capability. Once the guidewire 300 is in place,an access catheter can be introduced to the target lung tissue segmentas well. Since the guidewire has imaging capability, the access catheterneed not incorporate such imaging. This can be an advantage since itpermits the access lumen to be made larger since the catheter need notcarry any optical wave guides.

[0064] Referring now to FIG. 5A, a catheter 10 can be advanced to a lungtissue segment, specifically a diseased region DR, within a lung Lthrough a patient's trachea T. Advancement through the trachea T isrelatively simple and will optionally employ an endotracheal tube and/ora guidewire to select the advancement route through the branchingbronchus. The endotracheal tube may have a thin-walled design whereinthe inner diameter is larger than in standard endotracheal tubes.Standard endotracheal tubes have a 7.0 mm ID with a 10 mm OD. Thethin-walled design would have a 9.0 mm ID with a 10 mm OD; the larger IDallows the insertion of a larger instrument while providing adequateventilation. Steering can be effected under real time imaging using theimaging access catheters illustrated in FIGS. 3E and 3F. Optionally, theaccess catheter 10 may be introduced through a visualizing trachealtube, such as that described in U.S. Pat. No. 5,285,778, licensed to theassignee of the present application. As shown in FIG. 5B, thevisualizing endotracheal tube 120 includes an occlusion cuff 122 whichmay be inflated within the trachea just above the branch of the leftbronchus and right bronchus LB and RB, respectively. The visualizingendotracheal tube 120 includes a forward-viewing optical system,typically including both illumination fibers and an image fiber topermit direct viewing of the main branch between the left bronchus LBand right bronchus RB. Thus, initial placement of the access catheter 10can be made under visualization of the visualizing endotracheal tube 120and optionally the access catheter 10 itself. It may be appreciated thatthe access catheter may be positioned with or without the use of atrachea tube or similar device. When such a device is used, it may takea number of forms and may be positioned in a number of locations. Forexample, the trachea tube or device may be positioned as shown in FIG.5A, or it may be positioned to achieve “one lung ventilation” whereinthe side of the lung not involved in the corrective procedure will beproperly ventilated. Likewise, the access catheter may be positionedunder local anesthesia without intubation. In any case, referring againin particular to FIG. 5A, the access catheter 10 is advanced until itsdistal end 14 reaches a region in the bronchus or lung passageway whichleads directly into the diseased region DR.

[0065] Once the distal end 14 of the access catheter 10 is positioned ina desired location within the lung passageway, an obstructive device maybe deployed in the passageway. The method of deployment or delivery ofthe obstructive device is dependent on a number of factors, particularlythe design of the obstructive device itself. Typically, the obstructivedevice is housed within the access catheter 10 or within a catheter thatmay be passed through the access catheter 10. As depicted in FIG. 6, theobstructive device 150 may be compressed or collapsed within an interiorlumen of the access catheter 10. The obstructive device 150 depicted isone of many designs which may be utilized. The obstructive device 150may then be pushed out of the distal end 14 of the catheter 10, in thedirection of the arrow, into the lung passageway 152. If the device 150is self-expanding, for example by tension or shape-memory, the device150 will expand and anchor itself in the passageway 152. If the device150 is not self-expanding, it may be expanded with the use of a balloonor other mechanism provided by the access catheter 10, a catheter ordevice delivered through the access catheter 10, or another device.Similarly, the obstructive device 150 may be mounted or crimped over theaccess catheter 10 (not shown) or a delivery catheter and delivered tothe desired location. A sheath may then be placed over the device 150during insertion. Deployment of the device 150 may be achieved bywithdrawing the sheath and allowing the device 150 to self-expand orexpanding the device 150 with the use of a balloon or other mechanism.

[0066] A variety of embodiments of obstructive devices 150 are provided.To begin, a number of embodiments of the obstructive device 150 arecomprised of structural supports which expand to anchor the device 150in the passageway 152. Referring to FIG. 7A, the supports 154 may becomprised of radial segments 160 and longitudinal segments 162. Theradial segments 160 allow the device 150 to expand to fill thepassageway 152 and the longitudinal segments 162 rest against the wallsof the passageway 152 to help anchor the device 150. The supports 154may be individual, as shown in FIG. 7A, or may be connected to oneanother, as shown in FIG. 7B, for example. In addition, the supports 154may continue along a proximal end 164 and distal end 166 of the device150, as shown in FIG. 7A, or the supports 154 may not be present at suchends 164, 166, as shown in FIG. 7B.

[0067] Referring to FIGS. 8-11, the supports 154 may be comprised of amesh 170 or similar interlocking structure. As shown in FIG. 8, the mesh170 may be coiled or rolled into a cylindrical shape to fit within aninner lumen of a delivery or access catheter or to be mounted on the endof a such a delivery or access catheter. In either case, the device 150may be released within the lung passageway 152 where the mesh 170expands, uncoils and/or unrolls to fill the passageway 152. Such releasemay allow self-expansion or may involve the use of mechanical means toexpand the mesh 170. The expanded device 150 may fill the passageway 152in a generally cylindrical shape, as shown in FIG. 9, in single ordouble conical shape, as shown in FIG. 10, or it may form a variety ofother shapes, an example of which is shown in FIG. 11.

[0068] Referring now to FIG. 12, the supports 154 may be a helix orspiral 171 comprised of helically wound or spiral wound wire. The spiral171 may be compressed in a number of ways to load the spiral 171 withina lumen or on a distal end of a delivery catheter. For example, thespiral 171 may be wound tightly, similar to a watch spring, to reducethe cross-section of the spiral and provide spring tension. Upon releaseof the spiral 171, the coils 173 expand to contact the walls of thepassageway 152 and anchor the device 150.

[0069] In any of the above embodiments, the supports 154 may beconnected to, encapsulated in, coated or impregnated with a material toprevent flow of gases or liquids through the structural supports 154,thereby providing an obstruction. In addition, the material may includean antibiotic agent for release into the lung passageway. Examples ofobstructive materials include a thin polymer film 156, such as webbingbetween the structural supports 154, which may be used to seal againstthe surface of the lung passageway 152. Such a design is depicted inFIGS. 7A-7B, 10 and 12. Similarly, the structural supports 154 may befilled with an adhesive or sealant which will adhere the structuralsupport members together and prevent flow or gasses or liquids throughthe device 150. This is particularly useful in coiled or mesh designs inwhere the structural support members are relatively close together.Alternatively, as shown in FIG. 9 and FIG. 11, the supports 154 may beencased in a sack 158 comprised of a thin polymer, foam or othermaterial. Expansion of the supports 154 within the sack 158 presses thesack 158 against the walls of the passageway 152 forming a seal. In FIG.9, the sack 158 has been extended beyond the ends of the rolled supportstructure 154 for illustration purposes to differentiate between thesack 158 and support structure 154. However, typically, the supportstructure 154 will fill the sack 158. Again, the presence of the sack158 prevents flow of gases or liquids through the supports 154, therebyproviding an obstruction. It may be appreciated that the structuralsupports may comprise a variety of designs, creating devices 150 ofvarious lengths and shapes. Alternatively, the sack 158 may be utilizedwithout structural supports 154. The sack may expand to fill thepassageway by a variety of methods and may be held in position byimpregnation with an adhesive or other material. Such impregnation mayrigidify or support the sack to provide obstruction of the lungpassageway.

[0070] In addition and also shown in FIGS. 7A, 7B, 9, 11-13, a number ofembodiments of the obstructive device 150 include an inlet port 172,located near the proximal end 164, and an outlet port 174, located nearthe distal end 166. Such ports 172, 174 may be of any size or shape butare typically round or oval and are often located near the center of thepassageway 512 lumen for ease of accessibility. Some devices 150 mayonly include an inlet port 172 near the proximal end 164, as shown inFIG. 13. In this case, the distal end 166 is expanded to contact thewalls of the lung passageway 152 and anchor the device 150. Thus, theobstruction device 150 appears to have a cone shape with the inlet port172 at the apex of the cone. To ensure concentric placement of theobstruction device 150, the device 150 should contact the walls of thepassageway 152 for a length of at least 1.0 to 1.5 times the internaldiameter of the passageway that the device 150 occupies.

[0071] The inlet port 172, outlet port 174 or both may comprise amembrane or septum 176 covering the opening of the port. The septum 176will typically be self-sealing. One type of self-sealing septum 176comprises a solid membrane 178, illustrated in FIG. 14A. Other typescomprise pre-cut membranes in which the septum 176 includes cuts 180 orslits, as shown in FIGS. 14B and 14C. Such cuts 180 may allow ease ofpenetration through the septum 176 by an access tube or penetratingelement, as will be later described, while preventing flow through theseptum when the penetrating element is removed.

[0072] After the obstruction device 150 is deployed and anchored withina lung passageway 152 leading to a lung tissue segment, the device 150may be left as an implant to obstruct the passageway 152 from subsequentairflow. Airflow may include air and/or any other gas or combination ofgases, such as carbon dioxide. However, immediately after placement orat any time thereafter, the above described embodiments of the device150 may be accessed to aspirate the lung tissue segment through theobstructive device 150. This will cause the segment to at leastpartially collapse as part of a method for lung volume reduction.Aspirating through the obstructive device 150 may be accomplished by avariety of methods. For example, referring to FIG. 15, aspiration may beachieved by first inserting a penetration element, needle or access tube200 through the septum 176 of the inlet port 172. Positioning of theaccess tube 200 for such insertion may be achieved by any method,however, the access tube 200 is typically positioned by inserting theaccess tube 200, or a catheter carrying the access tube 200, through alumen in the access catheter 10 until it passes out of the distal end14. Inflating the balloon 18 on the access catheter 10 may center thedistal end 14 of the catheter in the lung passageway 152. If the inletport 172 is similarly centered, the access tube 200 may be passeddirectly out of the catheter 10 and through the septum 176 of the inletport 172.

[0073] If the septum 176 is a solid membrane 178, the access tube 200may be sharp enough to puncture or pierce the membrane 178. If theseptum 176 has cuts 180 or slits, the access tube 200 may be pushedthrough the cuts 180. In either case, the membrane or septum 176 willseal around the access tube 200. If the obstruction device 150 also hasan outlet port 174, the access tube 200 may optionally be passed throughboth the inlet and outlet ports 172, 174. Once the access tube 200 isinserted, gases and/or liquids may be aspirated through the access tube200 from the lung tissue segment and associated lung passageways.Optionally, prior to aspiration, a 100% oxygen, Helium-Oxygen mixture orlow molecular weight gas washout of the lung segment may be performed byintroducing such gas through the access tube 200. In this case,aspiration would removed both the introduced gas and any remaining gas.Similarly, liquid perfluorocarbon or certain drugs, such as antibiotics,may be introduced prior to aspiration. This may allow access to thecollapsed lung segment at a later time, for example, in the case of aninfection. In most cases, aspiration will at least partially collapsethe lung segment, as previously described. The access tube 200 may thenbe withdrawn. The septum 176 of the inlet port 172 and/or outlet port174 will then automatically seal, either by closing of the puncture siteor by closure of the cuts. Optionally, the ports may be additionallysealed with a sealant or by use of a heat source or radiofrequencysource.

[0074] Referring to FIGS. 16 and 17, aspiration through the obstructivedevice 150 may be achieved by contacting the obstructive device 150 witha suction tube or aspiration catheter 202 and aspirating gas or liquidsthrough the device 150. As shown in FIG. 16, the distal end 204 of theaspiration catheter 202 may be held against the inlet port 172.Positioning of the aspiration catheter 202 for such contact may beachieved by any method, however the catheter 202 is typically positionedin a manner similar to the access tube described above. By holding theaspiration catheter 202 against the port 172, a seal may be created andgases and/or liquids may be aspirated from the lung tissue segmentthrough the device 150. In this case, the inlet port 172 and the outletport 174, if present, must not be covered by a solid membrane 178. Ifcuts 180 are present, the gas or liquid may flow through the port due tothe pressure of the suction. As shown in FIG. 17, the distal end 204 ofthe aspiration catheter 202 may be slid over the inlet port 172 to forma seal. Again, gases and/or liquids may then be aspirated through thedevice 150 in a similar manner. The aspiration catheter 202 may then bewithdrawn. The septum 176 of the inlet port 172 and/or outlet port 174will then automatically seal, typically by closure of the cuts.Optionally, the ports may be additionally sealed with a sealant or byuse of a heat source or radiofrequency source.

[0075] Referring to FIGS. 18A-18C, the obstruction device 150 maybedeployed, anchored and aspirated therethrough while connected to anaspiration catheter 210. In this case, the access catheter 10 ispositioned within the lung passageway 152 at a desired location. If thecatheter 10 has an inflatable occlusion balloon 18 near its distal end14, the balloon 18 may be inflated to secure and center the catheter 10within the passageway 152; however, this step is optional. As shown inFIG. 18A, an aspiration catheter 210 carrying an obstruction device 150is then introduced through a lumen in the access catheter 10. As shownin FIG. 18B, the aspiration catheter 210 is advanced so that theobstruction device 150 emerges from the distal end 14 of the accesscatheter 10 and deploys within the lung passageway 152. Expansion andanchoring of the obstruction device 150 within the passageway 152 may beachieved by self-expansion or by expansion with the aid of a balloon,for example. The lung tissue segment isolated by the device 150 is thenaspirated through the device 150 and the attached aspiration catheter210. Such aspiration may remove air, gases, or liquids from the segmentand lung passageway 152 to at least partially collapse the lung segment.As shown in FIG. 15C, the obstruction device 150 is then detached fromthe aspiration catheter 210 and left behind in the passageway 152. Theproximal end 164 of the obstruction device 150 may comprise an inletport 172 which would allow subsequent access to the isolated lung tissuesegment at a later time. Alternatively, the proximal end 164 maycomprise a sealed end, wherein the obstruction device 150 may not besubsequently accessed and may provide long-term isolation of theterminal lung tissue segment.

[0076] It may be appreciated that the above described method may besimilarly achieved without the use of an aspiration catheter 210. Inthis case, the obstruction device 150 may be carried directly by theaccess catheter 10 and may be deployed while remaining attached to theaccess catheter 10. Aspiration may be achieved through the obstructiondevice 150 and the access catheter 10 to remove gases from the isolatedlung tissue segment and passageway 152. The obstructive device 150 maythen be detached from the access catheter 10 and left behind in thepassageway 152 for subsequent access or simple occlusion.

[0077] At this point, all catheters and instruments may be withdrawnfrom the patient and the obstruction device 150 may remain in itsanchored position, as described. The obstruction device 150 willessentially occlude the lung passageway 152 and prevent the inflow oroutflow of air or gases to the isolated lung tissue segment or diseasedregion DR. This may be effective in maintaining the desired level ofcollapse of the lung tissue segment to achieve lung volume reduction.However, at any point, the lung tissue segment may be reaccessed and/orreaspirated by repeating the steps described above. In addition, at anypoint, the obstruction device 150 may be removed from the lungpassageway 152, either by collapse of the expandable structure or byother means.

[0078] Additional embodiments of the obstructive device 150 arecomprised of a unidirectional valve. The valve may be operated uponaccess or it may operate in response to respiration. For example, whenthe valve is positioned in the lung passageway, the valve may beaccessed by engaging an aspiration catheter or a coupling member to thevalve. Aspiration through the aspiration catheter or coupling memberthen opens the valve to remove gases and/or liquids from the isolatedlung segment. Alternatively, the valve may open automatically inresponse to respiration. The valve may open during expiration to allowoutflow of gas from the lung segment and the close during inspiration toprevent inflow of gas to the lung segment. In either case, theunidirectional valves may take a number of forms.

[0079] One embodiment of such a unidirectional valve is illustrated inFIGS. 19A-19C. In this embodiment, the unidirectional valve 230,front-view shown in FIG. 19A, is comprised of a port 232 and a flexiblelayer 233 which is attached to the port 232 by at least one point ofconnection 234. As shown, the flexible layer 233 may be attached to thefront surface of the port 232 at four symmetrical points of connection234. In preferred embodiments, edges 236 of the layer 233 are positionedoutside of the opening of the port 232 (indicated by dashed lines). Thisprovides a desired seal when the valve is in the closed position.

[0080] Side-views shown in FIGS. 19B and 19C depict the valve 230 duringdifferent stages of the respiratory cycle. During expiration, the valve230 opens, as depicted in FIG. 19B. Here, expiration of gases isillustrated by arrows. Gases exiting through the lung passageway, withinwhich the valve 230 is positioned, apply force to the backside of theflexible layer 233 causing the layer 233 to expand outwardly away fromthe surface of the port 232 as shown. This allows the gases to flowthrough the spaces between the points of connection 234. Duringinspiration, the valve 230 closes, as depicted in FIG. 19C. Here,inspiration of air is illustrated by an arrow. Air entering the lungpassageway applies force to the front side of the flexible layer 233causing the layer 233 to seal against the surface of the port 232 asshown. This prevents gases from flowing through the valve 230.

[0081] Unidirectional valves 230 may be positioned in the lungpassageway 152 by methods similar to those previously described forother types of obstruction devices 150. As shown in FIG. 20, the valve230 may be positioned in the passageway 152 so that the outsideperimeter of the port 232 contacts the walls of the passageway 152. Inthis way, the valve 230 is essentially the size of the passageway lumenand provides the maximum area for potential flow-through of gas. Thevalve 230 is depicted in its open state, with gas flow traveling from anisolated lung tissue segment, through the valve and out of the patient'sairways. As shown in FIG. 21, the valve 230 may alternatively beattached to or part of structural supports 154 which expand radially toanchor the device 150 in the passageway 152. Such supports 154 aresimilar to those previously described. Again, the valve 230 is depictedin its open state. It may be appreciated that the valve 230 may be ofany size or shape and may substituted for any of the inlet and/or outletports previously described.

[0082] Another embodiment of a unidirectional valve is illustrated inFIGS. 22A-22B. In this embodiment, the valve 230 is comprised of a port232 and a flexible layer 233 as in the previous embodiment. However,here the flexible layer 233 has a series of holes 250 through the layer.In addition, the valve 230 is comprised of a partition 252 which alsohas holes 250. The holes 250 may be of any size, shape or arrangementthroughout the entire or a portion of the layer 233 and partition 252.The partition 252 covers the port 232 and the layer 233 is positionedover the partition 252, as illustrated in FIG. 22A and depicted byarrows, so that the holes 250 are substantially misaligned and thereforeblocked. The assembled valve, illustrated in FIG. 22B, does not have anythrough holes 250 in the closed position. The holes 250 in the layer 233are blocked by the underlying partition 252. Likewise, the holes 250 inthe partition 252 are blocked by the overlying layer 233. The layer 233is attached to the partition 252 and/or port 232 along its perimeter; itmay be a continuous attachment or may have discrete points of connectionwith spaces therebetween.

[0083] Side-views shown in FIGS. 23B and 23C depict the valve 230 duringdifferent stages of the respiratory cycle. During expiration, the valve230 opens, as depicted in FIG. 23B. Here, expiration of gases isillustrated by arrows. Gases exiting through the lung passageway, withinwhich the valve 230 is positioned, pass through the holes 250 in thepartition 252 and apply force to the backside of the flexible layer 233.This causes the layer 233 to expand outwardly away from the partition252 as shown. This allows the gases to flow through the holes 250 in thelayer 233. During inspiration, the valve 230 closes, as depicted in FIG.23C. Here, inspiration of air is illustrated by an arrow. Air enteringthe lung passageway applies force to the front side of the flexiblelayer 233 causing the layer 233 to seal against the surface of thepartition 252 as shown. This prevents gases from flowing through thevalve 230. This embodiment of a unidirectional valve 230 may bepositioned in a lung passageway 152 by methods similar to thosepreviously described for other types of obstruction devices 150,particularly as shown in FIGS. 20 and 21.

[0084] Although the unidirectional valves described above are shown asoperating during different stages of the respiratory cycle, the valvesmay additionally or alternatively be operated manually. Valvespositioned in a lung passageway, as depicted in FIGS. 20-21, may beaccessed by coupling an aspiration catheter to the valve. Coupling maycomprise engaging the aspiration catheter, a suitable catheter or acoupling member to the valve. In some cases, particularly when the valve230 comprises a port 232 which is smaller in diameter than the lumen ofthe lung passageway, as depicted in FIG. 21, the distal end of theaspiration catheter or coupling member may be slid over the port to forma seal. This was previously depicted in FIG. 17 in relation to sealingof the aspiration catheter 202 around an inlet port 172 of a non-valvedobstruction device. When a valve is present in this case, aspirationthrough the aspiration catheter will open the valve and draw gasesand/or liquids from the lung tissue segment. With the describedunidirectional valves 230, the suction force of the aspiration will drawthe flexible layer 233 away from the port 232 or the partition 252 toopen the valve.

[0085] Further embodiments of the obstructive device 150 are comprisedof a blockage device 280 having no ports through which aspiration of theisolated lung tissue segment may be achieved. After the blockage device280 is deployed and anchored within a lung passageway 152 leading to alung tissue segment, the device 280 is to be left as an implant toobstruct the passageway 152 from subsequent airflow. Although thepreviously described embodiments of obstructive devices 150 having inletand/or outlet ports 172, 174 may be utilized in a similar manner, theblockage device 280 may not be later accessed to aspirate the lungtissue segment through the device. An example of such a blockage device280 is illustrated in FIGS. 24 and 25.

[0086] As with the previous obstructive devices, the blockage device 280may be housed within the access catheter 10 or within a catheter thatmay be passed through the access catheter 10. As depicted in FIG. 24,the obstructive device 150 may be compressed or collapsed within aninterior lumen of the access catheter 10. The blockage device 280depicted is one of many designs which may be utilized. The blockagedevice 280 may then be pushed out of the distal end 14 of the catheter10, in the direction of the arrow, into the lung passageway 152. Thedevice 280 is to be self-expanding by tension or shape-memory so that itwill expand and anchor itself in the passageway 152.

[0087] Referring to FIG. 25, one embodiment of the blockage device 280comprises a coil 282. The coil 282 may be comprised of any type of wire,particularly superelastic or shape-memory wire, polymer or suitablematerial. The tension in the coil 282 allows the device 280 to expand tofill the passageway 152 and rest against the walls of the passageway 152to anchor the device 280. In addition, the coil 282 may be connected toa thin polymer film 284, such as webbing between the coils, to sealagainst the surface of the lung passageway 152. Such a film 284 preventsflow of gases or liquids through the coils, thereby providing anobstruction. Alternatively, as depicted in FIG. 25, the coil 282 may beencased in a sack 286. Expansion of the coil 282 within the sack 286presses the sack 286 against the walls of the passageway 152 forming aseal. Again, this prevents flow of gases or liquids, depicted by arrows,through the coil 282, thereby providing an obstruction. Similarly, asdepicted in FIG. 26, another embodiment of the blockage device 280comprises a mesh 283. The mesh 283 may be comprised of any type of wire,particularly superelastic or shape-memory wire, polymer or suitablematerial. The tension in the mesh 283 allows the device 280 to expand tofill the passageway 152 and rest against the walls of the passageway 152to anchor the device 280. In addition, the mesh 283 may be connected toa thin polymer film 284, such as webbing between the lattice of themesh, to seal against the surface of the lung passageway 152. Such afilm 284 prevents flow of gases or liquids through the mesh, therebyproviding an obstruction.

[0088] Referring now to FIG. 27, another embodiment of the blockagedevice 280 comprises a barb-shaped structure 304 designed to be wedgedinto a lung passageway 152 as shown. Such a structure 304 may becomprised of a solid material, an inflatable balloon material, or anymaterial suitable to provide a blockage function. The structure 304 maybe inflated before, during or after wedging to provide sufficientanchoring in the lung passageway. Similarly, the structure 304 may beimpregnated or infused with an adhesive or sealant before, during orafter wedging to also improve anchoring or resistance to flow of liquidsor gasses through the passageway 152.

[0089] Referring to FIG. 28, another embodiment of the blockage device280 comprises an inflated balloon. Such a balloon may take a number offorms. For example, the balloon may have take a variety of shapes, suchas round, cylindrical, conical, dogboned, or multi-sectional, to name afew. Or, a series of distinct or interconnected balloons may beutilized. Further, the surface of the balloon may be enhanced by, forexample, corrugation or texturing to improve anchoring of the balloonwithin the lung passageway. FIG. 28 illustrates a cylindrical-typeballoon 300 with textured friction bands 302 which contact the walls ofthe lung passageway 152 when the balloon 300 is inflated as shown.

[0090] It may be appreciated that such balloons may be inflated with annumber of materials, including saline, gas, suitable liquids, expandingfoam, and adhesive, to name a few. Further, a multi-layer balloon 310may be utilized, as shown in FIG. 29, which allows the injection ofadhesive 312 or suitable material between an outer layer 314 and aninner layer 316 of the balloon 310. Such adhesive 312 may provide ahardened shell on the obstruction device 280 to improve its obstructionabilities. As shown, the balloon 310 may be inflated within the innerlayer 316 with a foam 318 or other material. Similarly, as shown in FIG.30, the outer layer 314 of the blockage device 280 may contain holes,pores, slits or openings 320 which allow the adhesive 312 to emergethrough the outer layer 314 to the outside surface of the multi-layerballoon 310. When the balloon 310 is inflated within a lung passageway152, the outer layer 314 of the balloon 310 will press against the wallsof the passageway 152 and the adhesive 312 will bond with the walls inwhich it contacts. Such adhesion is designed to improve anchorage andobstructive abilities of the blockage device 280.

[0091] It may also be appreciated that the above described blockagedevices may be impregnated, coated or otherwise deliver an antibioticagent, such as silver nitrate. Such incorporation may be by any meansappropriate for delivery of the agent to the lung passageway. Inparticular, a multi-layer balloon may be provided which allows theinjection of an antibiotic agent between an outer layer and an innerlayer of the balloon 310. As previously described and depicted in FIG.30, the outer layer 314 of the blockage device 280 may contain holes,pores, slits or openings 320 which allow the agent to emerge through theouter layer 314 to the outside surface of the multi-layer balloon 310.Thus, the agent may be delivered to the walls and/or the lungpassageway.

[0092] It may further be appreciated that the blockage device 280 maycomprise a variety of designs having various lengths and shapes. Inaddition, many of the designs illustrated for use as a blockage device280 may also be adapted with an aspiration port for use as described inrelation to the previously illustrated embodiments of obstructiondevices 150. For example, such a port 172 having a septum 176 is shownin FIG. 30. If the port is not accessed, the device simply serves as ablockage device 280. Thus, in some cases, blockage devices 280 andobstructive devices 150 are synonymous.

[0093] Referring now to FIG. 31, kits 400 according to the presentinvention comprise at least an obstruction or blockage device 500 andinstructions for use IFU. Optionally, the kits may further include anyof the other system components described above, such as an accesscatheter 10, guidewire 402, access tube 200, aspiration catheter 202 orother components. The instructions for use IFU will set forth any of themethods as described above, and all kit components will usually bepackaged together in a pouch 450 or other conventional medical devicepackaging. Usually, those kit components which will be used inperforming the procedure on the patient will be sterilized andmaintained sterilely within the kit. Optionally, separate pouches, bags,trays, or other packaging may be provided within a larger package, wherethe smaller packs may be opened separately and separately maintain thecomponents in a sterile fashion.

[0094] While the above is a complete description of the preferredembodiments of the invention, various alternatives, modifications, andequivalents may be used. Therefore, the above description should not betaken as limiting the scope of the invention which is defined by theappended claims.

What is claimed is:
 1. A method for lung volume reduction, said methodcomprising: deploying an obstructive device in a lung passageway to alung tissue segment; and aspirating the segment through the deployedobstructive device to at least partially collapse the lung segment.